src/vnet/devices/af_packet/device.c - fdio/vpp - Gitiles

 /*
  *------------------------------------------------------------------
  * af_packet.c - linux kernel packet interface
  *
  * Copyright (c) 2016 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *------------------------------------------------------------------
  */

 #include <linux/if_packet.h>
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 #include <net/if.h>
 #include <net/if_arp.h>

 #include <vlib/vlib.h>
 #include <vlib/unix/unix.h>
 #include <vnet/ip/ip.h>
 #include <vnet/ethernet/ethernet.h>

 #include <vnet/devices/af_packet/af_packet.h>

 #define foreach_af_packet_tx_func_error               \
 _(FRAME_NOT_READY, "tx frame not ready")              \
 _(TXRING_EAGAIN,   "tx sendto temporary failure")     \
 _(TXRING_FATAL,    "tx sendto fatal failure")         \
 _(TXRING_OVERRUN,  "tx ring overrun")

 typedef enum
 {
 #define _(f,s) AF_PACKET_TX_ERROR_##f,
   foreach_af_packet_tx_func_error
 #undef _
     AF_PACKET_TX_N_ERROR,
 } af_packet_tx_func_error_t;

 static char *af_packet_tx_func_error_strings[] = {
 #define _(n,s) s,
   foreach_af_packet_tx_func_error
 #undef _
 };


 u8 *
 format_af_packet_device_name (u8 * s, va_list * args)
 {
   u32 i = va_arg (*args, u32);
   af_packet_main_t *apm = &af_packet_main;
   af_packet_if_t *apif = pool_elt_at_index (apm->interfaces, i);

   s = format (s, "host-%s", apif->host_if_name);
   return s;
 }

 static u8 *
 format_af_packet_device (u8 * s, va_list * args)
 {
   s = format (s, "Linux PACKET socket interface");
   return s;
 }

 static u8 *
 format_af_packet_tx_trace (u8 * s, va_list * args)
 {
   s = format (s, "Unimplemented...");
   return s;
 }

 static uword
 af_packet_interface_tx (vlib_main_t * vm,
 			vlib_node_runtime_t * node, vlib_frame_t * frame)
 {
   af_packet_main_t *apm = &af_packet_main;
   u32 *buffers = vlib_frame_args (frame);
   u32 n_left = frame->n_vectors;
   u32 n_sent = 0;
   vnet_interface_output_runtime_t *rd = (void *) node->runtime_data;
   af_packet_if_t *apif =
     pool_elt_at_index (apm->interfaces, rd->dev_instance);
   clib_spinlock_lock_if_init (&apif->lockp);
   int block = 0;
   u32 block_size = apif->tx_req->tp_block_size;
   u32 frame_size = apif->tx_req->tp_frame_size;
   u32 frame_num = apif->tx_req->tp_frame_nr;
   u8 *block_start = apif->tx_ring + block * block_size;
   u32 tx_frame = apif->next_tx_frame;
   struct tpacket2_hdr *tph;
   u32 frame_not_ready = 0;

   while (n_left > 0)
     {
       u32 len;
       u32 offset = 0;
       vlib_buffer_t *b0;
       n_left--;
       u32 bi = buffers[0];
       buffers++;

       tph = (struct tpacket2_hdr *) (block_start + tx_frame * frame_size);

       if (PREDICT_FALSE
 	  (tph->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING)))
 	{
 	  frame_not_ready++;
 	  goto next;
 	}

       do
 	{
 	  b0 = vlib_get_buffer (vm, bi);
 	  len = b0->current_length;
 	  clib_memcpy ((u8 *) tph +
 		       TPACKET_ALIGN (sizeof (struct tpacket2_hdr)) + offset,
 		       vlib_buffer_get_current (b0), len);
 	  offset += len;
 	}
       while ((bi =
 	      (b0->flags & VLIB_BUFFER_NEXT_PRESENT) ? b0->next_buffer : 0));

       tph->tp_len = tph->tp_snaplen = offset;
       tph->tp_status = TP_STATUS_SEND_REQUEST;
       n_sent++;
     next:
       tx_frame = (tx_frame + 1) % frame_num;

       /* check if we've exhausted the ring */
       if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
 	break;
     }

   CLIB_MEMORY_BARRIER ();

   if (PREDICT_TRUE (n_sent))
     {
       apif->next_tx_frame = tx_frame;

       if (PREDICT_FALSE (sendto (apif->fd, NULL, 0,
 				 MSG_DONTWAIT, NULL, 0) == -1))
 	{
 	  /* Uh-oh, drop & move on, but count whether it was fatal or not.
 	   * Note that we have no reliable way to properly determine the
 	   * disposition of the packets we just enqueued for delivery.
 	   */
 	  vlib_error_count (vm, node->node_index,
 			    unix_error_is_fatal (errno) ?
 			    AF_PACKET_TX_ERROR_TXRING_FATAL :
 			    AF_PACKET_TX_ERROR_TXRING_EAGAIN, n_sent);
 	}
     }

   clib_spinlock_unlock_if_init (&apif->lockp);

   if (PREDICT_FALSE (frame_not_ready))
     vlib_error_count (vm, node->node_index,
 		      AF_PACKET_TX_ERROR_FRAME_NOT_READY, frame_not_ready);

   if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
     vlib_error_count (vm, node->node_index, AF_PACKET_TX_ERROR_TXRING_OVERRUN,
 		      n_left);

   vlib_buffer_free (vm, vlib_frame_args (frame), frame->n_vectors);
   return frame->n_vectors;
 }

 static void
 af_packet_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
 				   u32 node_index)
 {
   af_packet_main_t *apm = &af_packet_main;
   vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
   af_packet_if_t *apif =
     pool_elt_at_index (apm->interfaces, hw->dev_instance);

   /* Shut off redirection */
   if (node_index == ~0)
     {
       apif->per_interface_next_index = node_index;
       return;
     }

   apif->per_interface_next_index =
     vlib_node_add_next (vlib_get_main (), af_packet_input_node.index,
 			node_index);
 }

 static void
 af_packet_clear_hw_interface_counters (u32 instance)
 {
   /* Nothing for now */
 }

 static clib_error_t *
 af_packet_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index,
 				   u32 flags)
 {
   af_packet_main_t *apm = &af_packet_main;
   vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
   af_packet_if_t *apif =
     pool_elt_at_index (apm->interfaces, hw->dev_instance);
   u32 hw_flags;
   int rv, fd = socket (AF_UNIX, SOCK_DGRAM, 0);
   struct ifreq ifr;

   if (0 > fd)
     {
       vlib_log_warn (apm->log_class, "af_packet_%s could not open socket",
 		     apif->host_if_name);
       return 0;
     }

   /* if interface is a bridge ignore */
   if (apif->host_if_index < 0)
     goto error;			/* no error */

   /* use host_if_index in case host name has changed */
   ifr.ifr_ifindex = apif->host_if_index;
   if ((rv = ioctl (fd, SIOCGIFNAME, &ifr)) < 0)
     {
       vlib_log_warn (apm->log_class,
 		     "af_packet_%s ioctl could not retrieve eth name",
 		     apif->host_if_name);
       goto error;
     }

   apif->is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0;

   if ((rv = ioctl (fd, SIOCGIFFLAGS, &ifr)) < 0)
     {
       vlib_log_warn (apm->log_class, "af_packet_%s error: %d",
 		     apif->is_admin_up ? "up" : "down", rv);
       goto error;
     }

   if (apif->is_admin_up)
     {
       hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP;
       ifr.ifr_flags |= IFF_UP;
     }
   else
     {
       hw_flags = 0;
       ifr.ifr_flags &= ~IFF_UP;
     }

   if ((rv = ioctl (fd, SIOCSIFFLAGS, &ifr)) < 0)
     {
       vlib_log_warn (apm->log_class, "af_packet_%s error: %d",
 		     apif->is_admin_up ? "up" : "down", rv);
       goto error;
     }

   vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);

 error:
   if (0 <= fd)
     close (fd);

   return 0;			/* no error */
 }

 static clib_error_t *
 af_packet_subif_add_del_function (vnet_main_t * vnm,
 				  u32 hw_if_index,
 				  struct vnet_sw_interface_t *st, int is_add)
 {
   /* Nothing for now */
   return 0;
 }

 static clib_error_t *af_packet_set_mac_address_function
   (struct vnet_hw_interface_t *hi, char *address)
 {
   af_packet_main_t *apm = &af_packet_main;
   af_packet_if_t *apif =
     pool_elt_at_index (apm->interfaces, hi->dev_instance);
   int rv, fd = socket (AF_UNIX, SOCK_DGRAM, 0);
   struct ifreq ifr;

   if (0 > fd)
     {
       vlib_log_warn (apm->log_class, "af_packet_%s could not open socket",
 		     apif->host_if_name);
       return 0;
     }

   /* if interface is a bridge ignore */
   if (apif->host_if_index < 0)
     goto error;			/* no error */

   /* use host_if_index in case host name has changed */
   ifr.ifr_ifindex = apif->host_if_index;
   if ((rv = ioctl (fd, SIOCGIFNAME, &ifr)) < 0)
     {
       vlib_log_warn
 	(apm->log_class,
 	 "af_packet_%s ioctl could not retrieve eth name, error: %d",
 	 apif->host_if_name, rv);
       goto error;
     }

   clib_memcpy (ifr.ifr_hwaddr.sa_data, address, 6);
   ifr.ifr_hwaddr.sa_family = ARPHRD_ETHER;

   if ((rv = ioctl (fd, SIOCSIFHWADDR, &ifr)) < 0)
     {
       vlib_log_warn (apm->log_class,
 		     "af_packet_%s ioctl could not set mac, error: %d",
 		     apif->host_if_name, rv);
       goto error;
     }

 error:

   if (0 <= fd)
     close (fd);

   return 0;			/* no error */
 }

 /* *INDENT-OFF* */
 VNET_DEVICE_CLASS (af_packet_device_class) = {
   .name = "af-packet",
   .tx_function = af_packet_interface_tx,
   .format_device_name = format_af_packet_device_name,
   .format_device = format_af_packet_device,
   .format_tx_trace = format_af_packet_tx_trace,
   .tx_function_n_errors = AF_PACKET_TX_N_ERROR,
   .tx_function_error_strings = af_packet_tx_func_error_strings,
   .rx_redirect_to_node = af_packet_set_interface_next_node,
   .clear_counters = af_packet_clear_hw_interface_counters,
   .admin_up_down_function = af_packet_interface_admin_up_down,
   .subif_add_del_function = af_packet_subif_add_del_function,
   .mac_addr_change_function = af_packet_set_mac_address_function,
 };

 VLIB_DEVICE_TX_FUNCTION_MULTIARCH (af_packet_device_class,
 				   af_packet_interface_tx)
 /* *INDENT-ON* */

 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	*------------------------------------------------------------------
	* af_packet.c - linux kernel packet interface
	*
	* Copyright (c) 2016 Cisco and/or its affiliates.
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at:
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*------------------------------------------------------------------
	*/

	#include <linux/if_packet.h>
	#include <sys/socket.h>
	#include <sys/ioctl.h>
	#include <net/if.h>
	#include <net/if_arp.h>

	#include <vlib/vlib.h>
	#include <vlib/unix/unix.h>
	#include <vnet/ip/ip.h>
	#include <vnet/ethernet/ethernet.h>

	#include <vnet/devices/af_packet/af_packet.h>

	#define foreach_af_packet_tx_func_error \
	_(FRAME_NOT_READY, "tx frame not ready") \
	_(TXRING_EAGAIN, "tx sendto temporary failure") \
	_(TXRING_FATAL, "tx sendto fatal failure") \
	_(TXRING_OVERRUN, "tx ring overrun")

	typedef enum
	{
	#define _(f,s) AF_PACKET_TX_ERROR_##f,
	foreach_af_packet_tx_func_error
	#undef _
	AF_PACKET_TX_N_ERROR,
	} af_packet_tx_func_error_t;

	static char *af_packet_tx_func_error_strings[] = {
	#define _(n,s) s,
	foreach_af_packet_tx_func_error
	#undef _
	};


	u8 *
	format_af_packet_device_name (u8 * s, va_list * args)
	{
	u32 i = va_arg (*args, u32);
	af_packet_main_t *apm = &af_packet_main;
	af_packet_if_t *apif = pool_elt_at_index (apm->interfaces, i);

	s = format (s, "host-%s", apif->host_if_name);
	return s;
	}

	static u8 *
	format_af_packet_device (u8 * s, va_list * args)
	{
	s = format (s, "Linux PACKET socket interface");
	return s;
	}

	static u8 *
	format_af_packet_tx_trace (u8 * s, va_list * args)
	{
	s = format (s, "Unimplemented...");
	return s;
	}

	static uword
	af_packet_interface_tx (vlib_main_t * vm,
	vlib_node_runtime_t * node, vlib_frame_t * frame)
	{
	af_packet_main_t *apm = &af_packet_main;
	u32 *buffers = vlib_frame_args (frame);
	u32 n_left = frame->n_vectors;
	u32 n_sent = 0;
	vnet_interface_output_runtime_t rd = (void ) node->runtime_data;
	af_packet_if_t *apif =
	pool_elt_at_index (apm->interfaces, rd->dev_instance);
	clib_spinlock_lock_if_init (&apif->lockp);
	int block = 0;
	u32 block_size = apif->tx_req->tp_block_size;
	u32 frame_size = apif->tx_req->tp_frame_size;
	u32 frame_num = apif->tx_req->tp_frame_nr;
	u8 block_start = apif->tx_ring + block block_size;
	u32 tx_frame = apif->next_tx_frame;
	struct tpacket2_hdr *tph;
	u32 frame_not_ready = 0;

	while (n_left > 0)
	{
	u32 len;
	u32 offset = 0;
	vlib_buffer_t *b0;
	n_left--;
	u32 bi = buffers[0];
	buffers++;

	tph = (struct tpacket2_hdr ) (block_start + tx_frame frame_size);

	if (PREDICT_FALSE
	(tph->tp_status & (TP_STATUS_SEND_REQUEST \| TP_STATUS_SENDING)))
	{
	frame_not_ready++;
	goto next;
	}

	do
	{
	b0 = vlib_get_buffer (vm, bi);
	len = b0->current_length;
	clib_memcpy ((u8 *) tph +
	TPACKET_ALIGN (sizeof (struct tpacket2_hdr)) + offset,
	vlib_buffer_get_current (b0), len);
	offset += len;
	}
	while ((bi =
	(b0->flags & VLIB_BUFFER_NEXT_PRESENT) ? b0->next_buffer : 0));

	tph->tp_len = tph->tp_snaplen = offset;
	tph->tp_status = TP_STATUS_SEND_REQUEST;
	n_sent++;
	next:
	tx_frame = (tx_frame + 1) % frame_num;

	/* check if we've exhausted the ring */
	if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
	break;
	}

	CLIB_MEMORY_BARRIER ();

	if (PREDICT_TRUE (n_sent))
	{
	apif->next_tx_frame = tx_frame;

	if (PREDICT_FALSE (sendto (apif->fd, NULL, 0,
	MSG_DONTWAIT, NULL, 0) == -1))
	{
	/* Uh-oh, drop & move on, but count whether it was fatal or not.
	* Note that we have no reliable way to properly determine the
	* disposition of the packets we just enqueued for delivery.
	*/
	vlib_error_count (vm, node->node_index,
	unix_error_is_fatal (errno) ?
	AF_PACKET_TX_ERROR_TXRING_FATAL :
	AF_PACKET_TX_ERROR_TXRING_EAGAIN, n_sent);
	}
	}

	clib_spinlock_unlock_if_init (&apif->lockp);

	if (PREDICT_FALSE (frame_not_ready))
	vlib_error_count (vm, node->node_index,
	AF_PACKET_TX_ERROR_FRAME_NOT_READY, frame_not_ready);

	if (PREDICT_FALSE (frame_not_ready + n_sent == frame_num))
	vlib_error_count (vm, node->node_index, AF_PACKET_TX_ERROR_TXRING_OVERRUN,
	n_left);

	vlib_buffer_free (vm, vlib_frame_args (frame), frame->n_vectors);
	return frame->n_vectors;
	}

	static void
	af_packet_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
	u32 node_index)
	{
	af_packet_main_t *apm = &af_packet_main;
	vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
	af_packet_if_t *apif =
	pool_elt_at_index (apm->interfaces, hw->dev_instance);

	/* Shut off redirection */
	if (node_index == ~0)
	{
	apif->per_interface_next_index = node_index;
	return;
	}

	apif->per_interface_next_index =
	vlib_node_add_next (vlib_get_main (), af_packet_input_node.index,
	node_index);
	}

	static void
	af_packet_clear_hw_interface_counters (u32 instance)
	{
	/* Nothing for now */
	}

	static clib_error_t *
	af_packet_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index,
	u32 flags)
	{
	af_packet_main_t *apm = &af_packet_main;
	vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
	af_packet_if_t *apif =
	pool_elt_at_index (apm->interfaces, hw->dev_instance);
	u32 hw_flags;
	int rv, fd = socket (AF_UNIX, SOCK_DGRAM, 0);
	struct ifreq ifr;

	if (0 > fd)
	{
	vlib_log_warn (apm->log_class, "af_packet_%s could not open socket",
	apif->host_if_name);
	return 0;
	}

	/* if interface is a bridge ignore */
	if (apif->host_if_index < 0)
	goto error; /* no error */

	/* use host_if_index in case host name has changed */
	ifr.ifr_ifindex = apif->host_if_index;
	if ((rv = ioctl (fd, SIOCGIFNAME, &ifr)) < 0)
	{
	vlib_log_warn (apm->log_class,
	"af_packet_%s ioctl could not retrieve eth name",
	apif->host_if_name);
	goto error;
	}

	apif->is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0;

	if ((rv = ioctl (fd, SIOCGIFFLAGS, &ifr)) < 0)
	{
	vlib_log_warn (apm->log_class, "af_packet_%s error: %d",
	apif->is_admin_up ? "up" : "down", rv);
	goto error;
	}

	if (apif->is_admin_up)
	{
	hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP;
	ifr.ifr_flags \|= IFF_UP;
	}
	else
	{
	hw_flags = 0;
	ifr.ifr_flags &= ~IFF_UP;
	}

	if ((rv = ioctl (fd, SIOCSIFFLAGS, &ifr)) < 0)
	{
	vlib_log_warn (apm->log_class, "af_packet_%s error: %d",
	apif->is_admin_up ? "up" : "down", rv);
	goto error;
	}

	vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);

	error:
	if (0 <= fd)
	close (fd);

	return 0; /* no error */
	}

	static clib_error_t *
	af_packet_subif_add_del_function (vnet_main_t * vnm,
	u32 hw_if_index,
	struct vnet_sw_interface_t *st, int is_add)
	{
	/* Nothing for now */
	return 0;
	}

	static clib_error_t *af_packet_set_mac_address_function
	(struct vnet_hw_interface_t hi, char address)
	{
	af_packet_main_t *apm = &af_packet_main;
	af_packet_if_t *apif =
	pool_elt_at_index (apm->interfaces, hi->dev_instance);
	int rv, fd = socket (AF_UNIX, SOCK_DGRAM, 0);
	struct ifreq ifr;

	if (0 > fd)
	{
	vlib_log_warn (apm->log_class, "af_packet_%s could not open socket",
	apif->host_if_name);
	return 0;
	}

	/* if interface is a bridge ignore */
	if (apif->host_if_index < 0)
	goto error; /* no error */

	/* use host_if_index in case host name has changed */
	ifr.ifr_ifindex = apif->host_if_index;
	if ((rv = ioctl (fd, SIOCGIFNAME, &ifr)) < 0)
	{
	vlib_log_warn
	(apm->log_class,
	"af_packet_%s ioctl could not retrieve eth name, error: %d",
	apif->host_if_name, rv);
	goto error;
	}

	clib_memcpy (ifr.ifr_hwaddr.sa_data, address, 6);
	ifr.ifr_hwaddr.sa_family = ARPHRD_ETHER;

	if ((rv = ioctl (fd, SIOCSIFHWADDR, &ifr)) < 0)
	{
	vlib_log_warn (apm->log_class,
	"af_packet_%s ioctl could not set mac, error: %d",
	apif->host_if_name, rv);
	goto error;
	}

	error:

	if (0 <= fd)
	close (fd);

	return 0; /* no error */
	}

	/* INDENT-OFF */
	VNET_DEVICE_CLASS (af_packet_device_class) = {
	.name = "af-packet",
	.tx_function = af_packet_interface_tx,
	.format_device_name = format_af_packet_device_name,
	.format_device = format_af_packet_device,
	.format_tx_trace = format_af_packet_tx_trace,
	.tx_function_n_errors = AF_PACKET_TX_N_ERROR,
	.tx_function_error_strings = af_packet_tx_func_error_strings,
	.rx_redirect_to_node = af_packet_set_interface_next_node,
	.clear_counters = af_packet_clear_hw_interface_counters,
	.admin_up_down_function = af_packet_interface_admin_up_down,
	.subif_add_del_function = af_packet_subif_add_del_function,
	.mac_addr_change_function = af_packet_set_mac_address_function,
	};

	VLIB_DEVICE_TX_FUNCTION_MULTIARCH (af_packet_device_class,
	af_packet_interface_tx)
	/* INDENT-ON */

	/*
	* fd.io coding-style-patch-verification: ON
	*
	* Local Variables:
	* eval: (c-set-style "gnu")
	* End:
	*/